1. Field of the Invention
This invention relates to filter presses for separating solids from liquid and, more particularly, to an improved filter press wherein the filter plates of the press are suspended from overhead support beams.
2. State of the Art
Filter presses are well known for separating solids from liquid slurries and the like. Conventional filter presses generally include a series of parallel, vertically disposed filter plates supported on a frame. The filter plates are covered on both sides with a filtration medium which permits liquid to flow therethrough but prevents the flow of solids contained in the liquid. Each of the filter plates is formed to have a peripheral rim which extends completely about the perimeter of the plate and an inner recessed drainage face on both sides of the plate. Thus, when adjacent plates are brought together in abutting relationship, the rims of adjacent plates engage to form a liquid-tight seal while the recessed inner faces form feed chambers between adjacent plates.
For filtration, the individual filter plates of the press are brought together in abutting, sealing relationship by a closing device, typically a hydraulic ram. The liquid slurry or the like from which solids are to be removed is then fed under pressure into the chambers between adjacent plates. The pressure of the feed slurry forces the liquid to flow from the feed chambers through the filtration medium to be discharged from the press. The solids in the slurry are left behind in the chambers between the plates. Filtration proceeds until the chambers are filled with filter cake or until a predetermined terminal pressure is reached. The filtration cycle is then complete; the feed to the press is stopped, the filter plates are moved apart and the filter cake is removed from the press.
Primary considerations in the design of filter presses are ease of operation, ease of maintenance and the amount of time that elapses between the end of one and the beginning of the next filtration cycle. These factors are influenced to a great extent by the manner in which the filter plates are supported on the frame of the filter press and on the means utilized to move the individual filter plates into abutting relationship.
In one well-known type of filter press, the filter plates are supported, either slideably or by means of rollers, on two horizontal siderails which extend along the vertical sides of the filter plates between two end support members. In this type of press, the filter plates can be removed only from the top of the press.
In another type of filter press, the filter plates are suspended, either slideably or by means of rollers, from one or more horizontal beams located directly above the filter plates and extending between two end support members. In this type of press, the plates can be removed only from the sides of the press.